CVE Vulnerabilities

CVE-2021-29648

Improper Restriction of Excessive Authentication Attempts

Published: Mar 30, 2021 | Modified: Nov 07, 2023
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
4.9 MEDIUM
AV:L/AC:L/Au:N/C:N/I:N/A:C
RedHat/V2
RedHat/V3
Ubuntu

An issue was discovered in the Linux kernel before 5.11.11. The BPF subsystem does not properly consider that resolved_ids and resolved_sizes are intentionally uninitialized in the vmlinux BPF Type Format (BTF), which can cause a system crash upon an unexpected access attempt (in map_create in kernel/bpf/syscall.c or check_btf_info in kernel/bpf/verifier.c), aka CID-350a5c4dd245.

Weakness

The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame, making it more susceptible to brute force attacks.

Affected Software

Name Vendor Start Version End Version
Linux_kernel Linux * 5.11.11 (excluding)

Potential Mitigations

  • Common protection mechanisms include:

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • Consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator. [REF-45]

References